Means for controlling the air-supply to locomotive-boiler furnaces.



J. H. HUME.

MEANS FOR GONTROLLING THE AIR SUPPLY T0 LOCOMOTIVE BOILER FURNACES.

APPLICATION rum DE0.14,1909.

1,028,881, Patented June 11,1912.

2 SHEETSWSHEET 1V NYENTOR.

I mw #Amis HowDEN HUME.

Att or nay..

J. H. HUME. MEANS POB. CONTROLLING TBE AIB. SUPPLY T0 LOGOMOTIVE BOILER FURNACES.

APPLIGATION FILED DEC.14, 1909 2 SHEETS-CHEBT 2.

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' hw E1n-om` JAMES HowDEN HumeI Attorney,

Patented June 11, 1912.

JAMES HOWDEN HUME, OF GLASGOW, SCOTLAND.

MEANS FOR CONTROLLING THE AIR-SUPPLY TO LOCOMOTIVE-BOILER FURNACES.

Specification of Letters Eatent.

Application filed December 14, 1909.

Patented June 11. 1912.

Serial No. 533,089.

To al?, whom it 'may concern:

Be it known that I, JAMES HownnN HUME, a subject of the King of the United Kingdom of Great Britain and Ireland, and residing at Glasgow, Scotland; have invented a certain new and useful Improved Means for Controlling the Air-Supply to Locomotive-Boiler Furnaces, of which the following is a specication.

In locomotive boiler furnacesI worked under forced draft, `as in Howdens forced draft system, provision must be made for closing the air inlet valves while the furnace door is open for firing the furnace in order to obviate risk of injury to the firemen by blowing back of the flames, and for that purpose interlocking devices are employed to insure that the inlet valves shall be closed before the door can be opened. As in such furnaces the firing operation must be frequently repeated, and the tiring door is open for relatively long periods, the advantage of the forced draft system is thus in large measure lost. To overcome that objection and provide means whereby enhanced draft, over natural draft, may be maintained at all times even during firing operations, we apply to` locomotive boiler furnaces an arrangement comprising the combination with interconnected devices for controlling the forced and induced drafts of means hereinafterv described for at the same time controlling the fire door.l

The invention is illustrated in the accompanying drawings in whichvw Figure 1 is a part longitudinal elevation, part vertical sectionon the line Fig. 2, and Fig. 2 is an end elevation, of a locomotive boiler provided with the improved means for controlling the air supply to the furnace; Figs..3, 4 and 5 are details showing the forced draft and auxiliary air inlet1 valves in various positions; Fig. 6 is a vertical section through the middle of the furnace door and through the forced draft supply trunk; Fig. 7 is a vertical section at right angles to Fig. 7 of the furnace door casing; Fig. 8 is a detail view of the valve for controlling the induced draft and Fig. 9 is a diagram showing the connections between the valves for controlling the induced draft and forced draft, and the relative posit-ions of said valves.

Referring to the drawings, forced draft r air is led to the furnace as from a fan a,

Fig. l, which may be located at the front of the boiler through a trunk A and branch trunks A1, and is admitted to the furnace beneath the grate by means of a valve A2, shown more particularly in Figs. (i and 9, adapted to be operated inlknown'manner as by means of a lever D and other devices hereinafter referred to.

The interlocking means for preventing opening of the furnace door B comprise a guard C attached to the operating lever D, said guard being arranged to extend, e. l(1. in front of the door latch E. The lever D is connected by means of a link F to a lever arm G of a cock or valve H on a steam pipe, which, when the cock or valve is open, as shown in Fig. 8, supplies steam, from the boiler by means of a pipe I to tin induced draft jet device J'. The valve levers are so arranged and connected that 'when the valve A2 is opened to admit the forced draft air supply, the steam supply valve H is closed, as shown in Fig. 9, and vice versa. As shown nin Figs. l and 2, the valve A2 is closed, and when in this position the door latch E can be raised clear of the guard C, thus permitting the furnace door to be opened.

In order to permit of regulating the volume of air to be supplied through the trunks M1, valves K operated by hand levers L are fitted in said trunks. To provide for a supply of air to the underside of the fire grate N, when the furnace door B is open and the induced draft system is in operation, the usual auxiliary valve means for admitting air at atmospheric pressure are fitted at. the base of the fire box and connected to the devices controlling the forced draft air inlet valve A2 and steam cock H. In express locomotives which are driven mainly with the boiler at the forward end, a single-auxiliary air admission valve may be provided .at the forward end only; but for locomotives which are used fory short journeys and which often run with the tender in front, a pluralityof air admission openings are preferably provided at each end, as shown, and

yare adapted to be closed by means of valves O and P, which valves are secured to spindles O1, I, respectively, and are coupled by a lever O2 secured to said spindle 01, one arm of a bell crank lever P2 secured to said spindle P1, and by a connecting link M, so that to suit the direction of running (indicated by the arrow R), when the valves O at one end are opened, the valves l at the @flier end are cloSeiil indicaecl in Figs, l., 4 and 5, or vice rerua, as indicated in Fig. 3. The said valves are preferably operated by means` of an independent hand lever S, a link S1, and 'the other arm of said hell crank lever P2. Valves U and V are interA connected by means 0f levers Ul, V1, and a link Q, and are adapted te be. controlled hy means of the lever D so aS to close said auxiliary 'valve upeninga, when the f rced draft System is in Operation, as indicated in Fig. 5; said valve 0r valves beingv preferably operated by means of a rnd lf" connected by a lpin un the, lever l) to a lever arm T which Secured tu the Spindle of the valve 'l.

As Shown }r)arlieularly in Figs. 8 and D, the casing of the. furnace duur is made hulA lfm! and is; adayded by ineaml of a branch trunk {l} in eunununieafel willi ille forced dra'fL air which may hus enfer (he furnace uy ray of a 'nninually-nY` ruled valve and liv perform in aid easing, Said valve lk i `Lly to pern'nt, nir te, enter deer opening uut sulif Le prevent llrinvirig` hac-'rg of Sniulic or the like when the furnace duur upened.

.ll-using n-:rw described my iwcnfion what l Claim and desirel lo secure by Letters latA L 't il? the lflnied Siate.: is:m

l. ln a. lucon'iotive beller furnace having a a forced draft to said furnace, a \^alve ccntrelling" an induced drafl tu 5ai 1l"furnace, :i guard fur locking' the fire duur, an Operating lever cunneelcd l; `:aid guard, and links cenneeling Said lever with said valves, whereby when said guard is in position to luck the fire door the fnrced draft is in operation, and when Said guard i5 in unlocking posiliu-n the induced draftis in operation.

Q. ln a locomotive boiler furnace having a fire deur, and a fire bex with Openings below the Same, in combination, a valve Controlling a forced draft te, said furnace, a valve, cnnlrulling an induced draft. to Said furnace, a guard fur leal-:ing the fire door, an Operating lever connected fo Said guard, linka` cnnnediing bolli Said valves with Asaid guard wlm-reby when Said guard is in position tu luck lhe fire duur llie forced draft i:-; in mineralien, and when l@aid guard is in unlwlung pusition lhe induced draft is in opcralinu, valves controlling ihe said openA ings; iu the [hehex and links connecing' said valws with Said lever.

ln tesiiniuny whereof lY have Signed my name io l'hisnspefrzilieaihn in flic preence ef uw subaru-living wilnesaffa.

JAMES IIUWDEN llUME,

lVilnc-se Vi Linen CnAxs'rn N l `i\ i I: wici'rn un, JQUN /lCCLrmny, Jr. 

